Anemia is frequent in pediatric patients following cardiac surgery. Despite frequent transfusions, the optimal hemoglobin threshold where benefits surpass risks is still unknown for these patients. Recently, Lacroix et al. showed that a restrictive transfusion strategy was not inferior to a liberal strategy concerning the development or progression of multiple organ dysfunction syndrome (MODS) and mortality in pediatric intensive care patients. In the absence of evidence, the aim of this study was to determine the impact of a restrictive versus a liberal transfusion strategy on new or progressive multiple organ dysfunction syndrome (MODS) in children following cardiac surgery. We conducted a subgroup analysis of the postoperative cardiac surgery patients of the Transfusion Requirements in Pediatric Intensive Care Unit (TRIPICU) study. Our study showed no statistically and clinically significant differences in the number of patients who acquired or worsened MODS, nor secondary outcomes between a restrictive and a liberal transfusion strategy. This subgroup analysis generates a research hypothesis that should be confirmed by a randomized controlled trial.